Something that would be neat for the YouTube collections that I think I've mentioned before would be ones honoring the works of the Muppet performers, especially long-time performers like Jim Henson, Frank Oz, Jerry Nelson, Richard Hunt, and Caroll Spinney (why do I have a feeling that a collection honoring Jim Henson would be saved for either the week of May 16 or September 24?).
But I've also been thinking right now that it'd be cool if they could do special compilations based around directors and writers. There are a lot of segments where we don't know who wrote or directed them (I have a feeling that the scripts only credit the writer of the main storyline and not inserts, even though it's clear insert scripts are included in the main episode scripts).
Not to mention compilations based on songs from different songwriters (I could see ones for the songs of Joe Raposo and Jeff Moss, but it'd be great if they'd honor some of the more underrated songwriters as well) or animators.
And it would be cool if they did one showing clips of cameo appearances by Muppet performers and crew members.